Extra-Virgin Olive Oil Reduces Glycemic Response to a High-Glycemic Index Meal in Patients With Type 1 Diabetes: A Randomized Controlled Trial

Eating habits and sleep quality in individuals with type 1 diabetes on continuous glucose monitoring and insulin pump

BACKGROUND AND AIMS

Sleep disorders are bidirectionally linked with eating behaviors and glucose metabolism, which could be clinically relevant in type 1 diabetes (T1D). We investigated the relationship between dietary habits and sleep quality in individuals with T1D on insulin pumps and continuous glucose monitoring (CGM).

METHODS AND RESULTS

In a cross-sectional study, dietary habits (7-day food diary, EPIC questionnaire) and sleep quality (Pittsburgh Sleep Quality Index questionnaire) were assessed in 59 men and 58 women with T1D, aged 19-79 years, using CGM and insulin pump. Differences in dietary habits and blood glucose after dinner (6 h) between participants differing in sleep quality, sleep duration, and sleep onset latency were evaluated. Bad Sleepers (n = 81) were twice as prevalent as Good Sleepers (n = 36) and had a significantly higher intake of fat than Good Sleepers (dinner: 30.7 ± 10.7 vs. 24.0 ± 10.5 g, p = 0.004). Short sleepers had a significantly higher usual intake (g/1000 kcal) of coffee and tea (90.4 ± 71.7 vs. 62.0 ± 35.6), alcoholic (47.8 ± 51.1 vs. 28.9 ± 31.5) and carbonated beverages (21.8 ± 38.1 vs. 9.3 ± 17.2) (p < 0.05 for all) than Long Sleepers. Long Sleep Onset Latency was associated with a significantly higher fat intake at dinner (41.8 ± 7.4 vs. 38.1 ± 9.1 % total energy, p = 0.029) than Short Sleep Onset Latency. No significant differences in post-dinner blood glucose levels were detected between participants with good or bad sleep quality.

CONCLUSION

Sleep disruption is common in T1D and is associated with unhealthy dietary choices, especially at dinner, independently of post-dinner blood glucose control.

Factor Associated with Adherence to the Protein and Fat Counting Strategy by Adults with Type 1 Diabetes Mellitus

Carbohydrate counting is one of the dietary strategies used for the management of type 1 diabetes (T1DM), and counting proteins and fats allows individuals to achieve better glycemic and metabolic control, reducing glycemic variability and long-term complications. The aim of this paper is to analyze the factors associated with adherence to the protein- and fat-counting strategy in adults with T1DM. This cross-sectional study was conducted from November 2021 to June 2022 through an online questionnaire. We applied Pearson's Chi-square test with adjusted residual analysis and a binomial logistic regression test using SPSS software, version 24.0, considering p < 0.05 as indicative of statistical significance. There was an association between performing protein and lipid counting and having a higher education level, income exceeding three minimum wages, and having adequate glycated hemoglobin. Performing protein and lipid counting increased the chances of having adequate HbA1c by 4.3 times. Protein and lipid counting was a predictor of having adequate HbA1c. The results suggest that considering the practice of counting proteins and fats is important as a strategy to optimize glycemic control.

Exploring Nutritional Influence on Blood Glucose Forecasting for Type 1 Diabetes Using Explainable AI

Type 1 diabetes mellitus (T1DM) is characterized by insulin deficiency and blood sugar control issues. The state-of-the-art solution is the artificial pancreas (AP), which integrates basal insulin delivery and glucose monitoring. However, APs are unable to manage postprandial glucose response (PGR) due to limited knowledge of its determinants, requiring additional information for accurate bolus delivery, such as estimated carbohydrate intake. This study aims to quantify the influence of various meal-related factors on predicting postprandial blood glucose levels (BGLs) at different time intervals (15 min, 60 min, and 120 min) after meals by using deep neural network (DNN) models. The prediction models incorporate preprandial blood glucose values, insulin dosage, and various meal-related nutritional factors such as intake of energy, carbohydrates, proteins, lipids, fatty acids, fibers, glycemic index, and glycemic load as input variables. The impact of input features was assessed by exploiting eXplainable Artificial Intelligence (XAI) methodologies, specifically SHapley Additive exPlanations (SHAP), which provide insights into each feature's contribution to the model predictions. By leveraging XAI methodologies, this study aims to enhance the interpretability and transparency of BGL prediction models and validate clinical literature hypotheses. The findings can aid in the development of decision-support tools for individuals with T1DM, facilitating PGR management and reducing the risks of adverse events. The improved understanding of PGR determinants may lead to advancements in AP technology and improve the overall quality of life for T1DM patients.

Delayed prandial insulin boluses are an important determinant of blood glucose control and relate to fear of hypoglycemia in people with type 1 diabetes on advanced technologies

AIMS

Automated insulin delivery systems improve blood glucose control in patients with type 1 diabetes (T1D). However, optimizing their performance requires patient's proper compliance to meal insulin bolus administration. We explored real-life prevalence of delayed prandial boluses (DBs) in adults with T1D on advanced technologies, and their association with glycemic control and fear of hypoglycemia (FH).

METHODS

In the last two-week web-based reports of 152 adults with T1D on Hybrid Closed Loop Systems (HCLS) or Sensor Augmented Pump (SAP), DBs were identified when a steep increase in blood glucose occurred at CGM before the prandial bolus, and CGM metrics were evaluated. All participants completed an online questionnaire on FH.

RESULTS

Mean DBs over two weeks were 10.2 ± 4.7 (M ± SD, range 1-23) and more frequent in women than men (11.0 ± 4.6 vs. 9.4 ± 4.7, p = 0.036). Participants with more DBs (>12) showed significantly lower Time-In-Range (62.4 ± 13.8 vs. 76.6 ± 9.0 %) than those with less DBs (<7.7), along with higher Time-Above-Range, GMI, and Coefficient-of-Variation (ANOVA, p < 0.001 for all). Participants with higher FH score showed more DBs (11.6 ± 5.0) than those in lower tertiles (9.57 ± 4.59 and 9.47 ± 4.45, ANOVA p = 0.045).

CONCLUSIONS

In patients on advanced technologies, delayed boluses are extremely common, and associate with significantly worse glycemic control. Utmost attention is needed to bolus timing, mainly tackling fear of hypoglycemia.

Effect of Extra Virgin Olive Oil on Anthropometric Indices, Inflammatory and Cardiometabolic Markers: a Systematic Review and Meta-Analysis of Randomized Clinical Trials

BACKGROUND

A large body of literature associated extra virgin olive oil (EVOO) consumption with low risk of cardiovascular disease and mortality. However, findings from clinical trials related to EVOO consumption on blood pressure, lipid profile, and anthropometric and inflammation parameters are not univocal.

OBJECTIVES

The aim of this systematic review and meta-analysis was to evaluate the effect of EVOO consumption on cardiometabolic risk factors and inflammatory mediators.

METHODS

We searched PubMed/MEDLINE, Scopus, and Cochrane up through 31 March, 2023, without any particular language limitations, in order to identify randomized controlled trials (RCTs) that examined the effects of EVOO consumption on cardiometabolic risk factors, inflammatory mediators, and anthropometric indices. Outcomes were summarized as standardized mean difference (SMD) with 95% confidence intervals (CIs) estimated from Hedge's g and random-effects modeling. Heterogeneity was assessed by Cochran Q-statistic and quantified (I2).

RESULTS

Thirty-three trials involving 2020 participants were included. EVOO consumption was associated with a significant decrease in insulin (n = 10; SMD: -0.28; 95% CI: -0.51, -0.05; I2 = 48.57%) and homeostasis model assessment of insulin resistance levels (HOMA-IR) (n = 9; SMD: -0.19; 95% CI: -0.35, -0.03; I2 = 00.00%). This meta-analysis indicated no significant effect of consuming EVOO on fasting blood glucose, triglycerides, total cholesterol, low density lipoproteins, very low density lipoproteins, high density lipoproteins, Apolipoprotein (Apo) A-I and B, lipoprotein a, blood pressure, body mass index, waist circumference, waist to hip ratio, C-reactive protein, interleukin-6, interleukin-10, and tumor necrosis factor α levels (P > 0.05).

CONCLUSIONS

The present evidence supports a beneficial effect of EVOO consumption on serum insulin levels and HOMA-IR. However, larger well-designed RCTs are still required to evaluate the effect of EVOO on cardiometabolic risk biomarkers. This study was registered in PROSPERO as CRD42023409125.

EVOO supplement prevents type 1 diabetes by modulating gut microbiota and serum metabolites in NOD mice

AIMS

Extra virgin olive oil (EVOO) is the highest quality olive oil available and has been shown to regulate postprandial blood glucose in patients with type 1 diabetes (T1D). However, it remains uncertain whether EVOO can prevent the onset of T1D. In this study, we investigated the potential preventive effect of orally administered EVOO on T1D in non-obese diabetic (NOD) mice.

MAIN METHODS

We analyzed changes in fecal microbes using 16 s rDNA sequencing and serum metabolites using Ultra High-Performance Liquid Chromatography and Quadrupole Time-of-Flight Mass Spectrometry (Q-TOF-MS).

KEY FINDINGS

Our findings showed that EVOO supplementation in NOD mice slowed gastric emptying, reduced insulitis, and delayed T1D onset. Moreover, EVOO altered the composition of fecal microbes, increasing the Bacteroidetes/Firmicutes ratio, and promoting the growth of short-chain fatty acids (SCFAs)-producing bacteria, such as Lachnoclostridium and Ruminococcaceae_UCG-005. Moreover, it also increased beneficial serum metabolites, including unsaturated fatty acid and triterpenoid, which positively correlated with the increased SCFA-producing bacteria and negatively correlated with the disease indicators. Conversely, most decreased serum lipid metabolites, such as Oleamide, showed the opposite trend.

SIGNIFICANCE

Our study demonstrates that EVOO may ameliorate pancreas inflammation and prevent T1D onset in NOD mice by modulating gut microbiota and serum metabolites.

Identification of a Novel Score for Adherence to the Mediterranean Diet That Is Inversely Associated with Visceral Adiposity and Cardiovascular Risk: The Chrono Med Diet Score (CMDS)

Adherence to the Mediterranean diet (MedDiet) leads to reduction of mortality from all causes, especially in subjects with cardiovascular disease, obesity, and diabetes. Numerous scores have been proposed to evaluate the adherence to MedDiet, mainly focused on eating habits. In this study, we verified whether existing validated MedDiet scores, namely, MEDI-LITE and the Mediterranean Diet Score (MDS), could be associated with visceral adiposity. Failing to find a significant association with adiposity, we proposed the validation of a new, easy-to-use adherence questionnaire, the Chrono Med-Diet score (CMDS). CMDS contains eleven food categories, including chronobiology of dietary habits and physical activity. Compared to the MEDI-LITE score and MDS, low values of CMDS are linked to increased waist circumference (WC) and dysmetabolic conditions. CMDS was also inversely correlated with cardiovascular risk (CVR), as well as Fatty Liver Index (FLI). In conclusion, the CMDS is a novel questionnaire to study the adherence to the MedDiet that, focusing on type and timing of carbohydrates intake, has the peculiar capability of capturing subjects with abdominal obesity, thus being an easy-to-use instrument of personalized medicine.

Phytoestrogens, novel dietary supplements for breast cancer

While endocrine therapy is considered as an effective way to treat breast cancer, it still faces many challenges, such as drug resistance and individual discrepancy. Therefore, novel preventive and therapeutic modalities are still in great demand to decrease the incidence and mortality rate of breast cancer. Numerous studies suggested that G protein-coupled estrogen receptor (GPER), a membrane estrogen receptor, is a potential target for breast cancer prevention and treatment. It was also shown that not only endogenous estrogens can activate GPERs, but many phytoestrogens can also function as selective estrogen receptor modulators (SERMs) to interact GPERs. In this review, we discussed the possible mechanisms of GPERs pathways and shed a light of developing novel phytoestrogens based dietary supplements against breast cancers.

Dietary treatment of type 1 diabetes: Beyond carbohydrate counting to fight cardiovascular risk

AIMS

Type 1 diabetes (T1D) is tied to an increased risk of cardiovascular morbidity and mortality. Dietary treatment would be an elective therapeutic strategy to fight this risk. However, it is not known what the best dietary approach is. We revisited the currently available literature on the nutritional treatment of T1D in the light of their potential comprehensive effects on the management of cardio-metabolic risk factors (body weight, fasting and postprandial glucose and lipid metabolism).

DATA SYNTHESIS

Nutritional research in T1D is mainly focused on blood glucose control, with most of the trials aiming at evaluating the acute effects of nutrients on postprandial glycemic response. The effects of the quantity and quality of nutrients and some specific foods on other metabolic risk factors have been explored mainly in cross-sectional analysis. Very few well-designed nutritional trials evaluated the best dietary approach to comprehensively manage cardiovascular risk by targeting along with blood glucose control, overweight, fasting and postprandial dyslipidemia. Therefore, the current best practice guidance for the dietary management of cardiovascular risk in T1D is generally based on evidence from patients with type 2 diabetes.

CONCLUSIONS

Well-conducted nutritional trials specifically designed for T1D are needed to identify the best dietary treatment to fight cardiovascular risk in these patients.

Postprandial glucose variability in type 1 diabetes: The individual matters beyond the meal

AIM

To explore intraindividual (between-meals) and interindividual (between-subjects) variability of postprandial glucose response (PGR) in type 1 diabetes (T1DM).

METHODS

Data were taken from five cross-over trials in 61 subjects with T1DM on insulin pump wherein the effects of different dietary components or the intraindividual-variability of PGR to the same meal were evaluated by CGM. Predictors (type of meal or nutrient composition) of early (iAUC_0-3h), late (iAUC_3-6h), total (iAUC_0-6h), and time-course of postprandial blood glucose changes (iAUC_{3-6hminus0-3h}) were evaluated using two mixed-effect linear regression models considering the patient's identification number as random-effect.

RESULTS

High-glycemic-index (HGI) and low-glycemic-index meals were the best positive and negative predictors of glucose iAUC_0-3h, respectively. A Low-Fat-HGI meal significantly predicted iAUC_{3-6hminus0-3h} (Estimate 3268; p = 0.017). Among nutrients, dietary fiber was the only significant negative predictor of iAUC_0-3h (Estimate -550; p < 0.001) and iAUC_0-6h (Estimate -742; p = 0.01) and positive predictor of iAUC_{3-6hminus0-3h} (Estimate 336; p = 0.043). For all models, the random-effect patient was statistically significant (p < 0.001 by ANOVA).

CONCLUSION

Beyond the meal characteristics (including glycemic index, fat and fiber content), individual traits significantly influence PGR. Specific interindividual factors should be further identified to properly predict glucose response to meals with different composition in individuals with T1DM.

Differential Glycemic Effects of Low- versus High-Glycemic Index Mediterranean-Style Eating Patterns in Adults at Risk for Type 2 Diabetes: The MEDGI-Carb Randomized Controlled Trial

A Mediterranean-style healthy eating pattern (MED-HEP) supports metabolic health, but the utility of including low-glycemic index (GI) foods to minimize postprandial glucose excursions remain unclear. Therefore, we investigated the relative contribution of GI towards improvements in postprandial glycemia and glycemic variability after adopting a MED-HEP. We conducted a randomized, controlled dietary intervention, comparing high- versus low-GI diets in a multi-national (Italy, Sweden, and the United States) sample of adults at risk for type 2 diabetes. For 12 weeks, participants consumed either a low-GI or high-GI MED-HEP. We assessed postprandial plasma glucose and insulin responses to high- or low-GI meals, and daily glycemic variability via continuous glucose monitoring at baseline and post-intervention. One hundred sixty adults (86 females, 74 males; aged 55 ± 11 y, BMI 31 ± 3 kg/m2, mean ± SD) with ≥two metabolic syndrome traits completed the intervention. Postprandial insulin concentrations were greater after the high-GI versus the low-GI test meals at baseline (p = 0.004), but not post-intervention (p = 0.17). Postprandial glucose after the high-GI test meal increased post-intervention, being significantly higher than that after the low-GI test meal (35%, p < 0.001). Average daily glucose concentrations decreased in both groups post-intervention. Indices of 24-h glycemic variability were reduced in the low-GI group as compared to baseline and the high-GI intervention group. These findings suggest that low-GI foods may be an important feature within a MED-HEP.

Dietary determinants of postprandial blood glucose control in adults with type 1 diabetes on a hybrid closed-loop system

AIMS/HYPOTHESIS

The aim of this work was to assess the relationship between meal nutrients and postprandial blood glucose response (PGR) in individuals with type 1 diabetes on a hybrid closed-loop system (HCLS).

METHODS

The dietary composition of 1264 meals (398 breakfasts, 441 lunches and 425 dinners) was assessed by 7-day food records completed by 25 individuals with type 1 diabetes on HCLSs (12 men/13 women, mean ± SD age 40 ± 12 years, mean ± SD HbA_1c 51 ± 10 mmol/mol [6.9 ± 0.2%]). For each meal, PGR (continuous glucose monitoring metrics, glucose incremental AUCs) and insulin doses (pre-meal boluses, post-meal microboluses automatically delivered by the pump and adjustment boluses) over 6 h were evaluated.

RESULTS

Breakfast, lunch and dinner significantly differed with respect to energy and nutrient intake and insulin doses. The blood glucose postprandial profile showed an earlier peak after breakfast and a slow increase until 4 h after lunch and dinner (p < 0.001). Mean ± SD postprandial time in range (TIR) was better at breakfast (79.3 ± 22.2%) than at lunch (71.3 ± 23.9%) or dinner (70.0 ± 25.9%) (p < 0.001). Significant negative predictors of TIR at breakfast were total energy intake, per cent intake of total protein and monounsaturated fatty acids, glycaemic load and absolute amounts of cholesterol, carbohydrates and simple sugars consumed (p < 0.05 for all). No significant predictors were detected for TIR at lunch. For TIR at dinner, a significant positive predictor was the per cent intake of plant proteins, while negative predictors were glycaemic load and intake amounts of simple sugars and carbohydrate (p < 0.05 for all).

CONCLUSIONS/INTERPRETATION

This study shows that nutritional factors other than the amount of carbohydrate significantly influence postprandial blood glucose control. These nutritional determinants vary between breakfast, lunch and dinner, with differing effects on postprandial blood glucose profile and insulin requirements, thus remaining a challenge to HCLSs.

Does dietary fat cause a dose dependent glycemic response in youth with type 1 diabetes?

OBJECTIVE

To determine the glycemic impact of dietary fat alone consumed without prandial insulin in individuals with T1D.

RESEARCH DESIGN AND METHODS

Thirty participants with T1D (aged 8-18 years) consumed a test drink with either 20 g glucose or 1, 13, 26, 39, 51 g of fat with negligible carbohydrate/protein on 6 consecutive evenings, in a randomized order without insulin. Continuous glucose monitoring was used to measure glucose levels for 8 h postprandially. Primary outcome was mean glycemic excursion at each 30 min interval for each test condition. Generalized linear mixed models with a random effect for people with diabetes were used to test for an increase in blood glucose excursion with increasing quantity of fat.

RESULTS

Glycemic excursions after 20 g glucose were higher than after fat drinks over the first 2 h (p < 0.05). Glycemic excursion for the fat drinks demonstrated a dose response, statistically significant from 4 h (p = 0.026), such that increasing loads of fat caused a proportionally larger increase in glycemic excursion, remaining statistically significant until 8 h (p < 0.05). Overall, for every 10 g fat added to the drink, glucose concentrations rose by a mean of 0.28 mmol L^-1 from 330 min (95% CI 0.15 to 0.39, p < 0.001).

CONCLUSIONS

Fat ingested without other macronutrients increases glucose excursions from 4 to 8 h after ingestion, in a dose dependent manner. These observations may impact on insulin dosing for high-fat foods in individuals with T1D.

The effect of almond intake on glycemic control: A systematic review and dose-response meta-analysis of randomized controlled trials

Number trials have evaluated the effect of almond intake on glycemic control in adults; however, the results remain equivocal. Therefore, the present meta-analysis aims to examine the effectiveness of almond intake on glycemic parameters. Online databases including PubMed, Scopus, ISI web of science, Embase, and Cochrane Library were searched up to August 2021 for trials that examined the effect of almond intake on glycemic control parameters including fasting blood sugar (FBS), insulin, HOMA-IR, and HbA1C. Treatment effects were expressed as mean difference (MD) and the standard deviation (SD) of outcomes. To estimate the overall effect of almond intake, we used the random-effects model. In total, 24 studies with 31 arms were included in our analysis. The meta-analysis revealed that almond intake did not significantly change the concentrations of FBS, HbA1c, insulin levels, and HOMA-IR. In conclusion, there is currently no convincing evidence that almonds have a clear beneficial effect on glycemic control. Future studies are needed before any confirmed conclusion could be drowned.

Dietary Changes During COVID-19 Lockdown in Adults With Type 1 Diabetes on a Hybrid Artificial Pancreas

In this retrospective analysis, we examine the impact of the lockdown of the coronavirus pandemic (COVID-19) on eating habits in individuals with type 1 diabetes (T1D) on a hybrid artificial pancreas (HAP). Dietary composition before and during lockdown was assessed by 7-day food records of 12 participants with T1D on HAP (three men and nine women, ages 38 ± 13 years, HbA1c 6.8 ± 0.3%, M ± SD). Continuous glucose monitoring (CGM) metrics and lifestyle changes (online questionnaire) were also assessed. Compared to prelockdown, reported body weight tended to increase during lockdown with no changes in total energy intake. Participants significantly decreased animal protein intake (−2.1 ± 3.7% of total energy intake, p = 0.048), but tended to increase carbohydrate intake (+17 ± 28 g/day, p = 0.052). These changes were induced by modifications of eating habits at breakfast and lunch during weekdays. Patients consumed more cereals (+21 ± 33 g/day, p = 0.038), whole grain (+22 ± 32 g/day, p = 0.044), and sweets (+13 ± 17 g/day, p = 0.021), and less animal protein sources (−42 ± 67 g/day, p = 0.054). Participants showed a more regular meal timing and decreased physical activity. Blood glucose control remained optimal (time-in-range 76 ± 8 vs. 75 ± 7% before lockdown), and daily total insulin infusion increased (42 ± 10 vs. 39 ± 12 I.U., p = 0.045). During the lockdown, patients with T1D on HAP modified dietary habits by decreasing animal protein and increasing carbohydrate intake. This increase, mainly concerning whole grain and low-glycemic-index products, did not influence blood glucose control.

Additional Insulin Is Required in Both the Early and Late Postprandial Periods for Meals High in Protein and Fat: A Randomized Trial

CONTEXT

The pattern and quantity of insulin required for high-protein high-fat (HPHF) meals is not well understood.

OBJECTIVE

This study aimed to determine the amount and delivery pattern of insulin required to maintain euglycemia for 5 hours after consuming a HPHF meal compared with a low-protein low-fat (LPLF) meal.

METHODS

This randomized crossover clinical trial, conducted at 2 Australian pediatric diabetes centers, included 10 patients (12-21 years of age) with type 1 diabetes for ≥ 1 year. Participants were randomized to HPHF meal (60 g protein, 40 g fat) or LPLF meal (5 g protein, 5 g fat) with identical carbohydrate content (30 g). A modified insulin clamp technique was used to determine insulin requirements to maintain postprandial euglycemia for 5 hours. Total mean insulin requirements over 5 hours were measured.

RESULTS

The total mean insulin requirements for the HPHF meal were significantly greater than for the LPLF meal (11.0 [CI 9.2, 12.8] units vs 5.7 [CI 3.8, 7.5] units; P = 0.001). Extra intravenous insulin was required for HPHF: 0 to 2 hours (extra 1.2 [CI 0.6, 1.6] units/h), 2 to 4 hours (extra 1.1 [CI 0.6, 1.6] units/h), and 4 to 5 hours (extra 0.6 [CI 0.1, 1.1] units/h) after the meal. There were marked inter-individual differences in the quantity of additional insulin (0.3 to 5 times more for HPHF) and the pattern of insulin delivery (0%-85% of additional insulin required in the first 2 hours).

CONCLUSION

The addition of protein and fat to a standardized carbohydrate meal almost doubled the mean insulin requirement, with most participants requiring half of the additional insulin in the first 2 hours.

Effect of Extra Virgin Olive Oil and Butter on Endothelial Function in Type 1 Diabetes

Post-prandial hyperglycemia can be relevant in developing early manifestations of atherosclerosis. EVOO (Extra Virgin Olive Oil), rich in saturated fatty acids and commonly used in the Mediterranean diet, seems to control post-prandial hyperglycemia better than butter. Subjects with type 1 diabetes are at higher risk of developing cardiovascular disease and show endothelial dysfunction, an early manifestation of atherosclerosis in the first years of the disease. Our study aims to evaluate whether EVOO and butter influence endothelial function in subjects with type 1 diabetes when added to a single high glycemic index (HGI) meal. In this exploratory cross-over study, 10 subjects with type 1 diabetes and 6 healthy subjects were scheduled to receive two types of HGI meals: one enriched with EVOO and one with butter. Before and after each test meal at different time points, all subjects underwent the evaluation of endothelial function by flow-mediated dilation technique, glucose and lipids measurements, and gastric emptying assessment by ultrasound. Flow-mediated dilation significantly increased after EVOO-enriched meal compared with butter in subjects with type 1 diabetes (two-way-repeated measurements ANOVA, p = 0.007). In patients with type 1 diabetes, the add-on of EVOO to HGI meal improves vascular function compared to butter, which has detrimental effects.

In children and young people with type 1 diabetes using Pump therapy, an additional 40% of the insulin dose for a high-fat, high-protein breakfast improves postprandial glycaemic excursions: A cross-over trial

AIM

To determine the insulin requirement for a high-fat, high-protein breakfast to optimise postprandial glycaemic excursions in children and young people with type 1 diabetes using insulin pumps.

METHODS

In all, 27 participants aged 10-23 years, BMI <95^th percentile (2-18 years) or BMI <30 kg/m² (19-25 years) and HbA_1c ≤64 mmol/mol (≤8.0%) consumed a high-fat, high-protein breakfast (carbohydrate: 30 g, fat: 40 g and protein: 50 g) for 4 days. In this cross-over trial, insulin was administered, based on the insulin-to-carbohydrate ratio (ICR) of 100% (control), 120%, 140% and 160%, in an order defined by a randomisation sequence and delivered in a combination bolus, 60% ¼ hr pre-meal and 40% over 3 hr. Postprandial sensor glucose was assessed for 6 hr.

RESULTS

Comparing 100% ICR, 140% ICR and 160% ICR resulted in significantly lower 6-hr areas under the glucose curves: mean (95%CI) (822 mmol/L.min [605,1039] and 567 [350,784] vs 1249 [1042,1457], p ≤ 0.001) and peak glucose excursions (4.0 mmol/L [3.0,4.9] and 2.7 [1.7,3.6] vs 6.0 [5.0,6.9],p < 0.001). Rates of hypoglycaemia for 100%-160% ICR were 7.7%, 7.7%, 12% and 19% respectively (p ≥ 0.139). With increasing insulin dose, a step-wise reduction in mean glucose excursion was observed from 1 to 6 hr (p = 0.008).

CONCLUSIONS

Incrementally increasing the insulin dose for a high-fat, high-protein breakfast resulted in a predictable, dose-dependent reduction in postprandial glycaemia: 140% ICR improved postprandial glycaemic excursions without a statistically significant increase in hypoglycaemia. These findings support a safe, practical method for insulin adjustment for high-fat, high-protein meals that can be readily implemented in practice to improve postprandial glycaemia.

The effect of grapes/grape products on glycemic response: A systematic review and meta-analysis of randomized controlled trials

The aim of this study was to perform a systematic review and meta-analysis of randomized clinical trials (RCTs) to examine the effect of grapes/grape products supplementation on glycemic indices in adults. Our systematic search to find relevant RCTs was performed up to February 2020 using PubMed, Scopus, ISI Web of Science, Cochrane Library, and Google Scholar. Based on the heterogeneity between included studies, a random effects or a fixed model was applied in the meta-analysis, and results were expressed as weighted mean differences (WMD) with 95% confidence intervals (CI). Twenty-nine clinical trials (1,297 participants) fulfilled the eligibility criteria of the present meta-analysis. Overall, the grapes/grape products supplementation significantly reduced homeostatic model assessment of insulin resistance (HOMA-IR) (WMD: -0.54, 95% CI: -0.91, -0.17, p = . 004) but did not affect fasting insulin levels (WMD: -0.90 μIU/ml, 95% CI: -1.04, 2.84, p = .362) and hemoglobin A1C (Hb1Ac) percentage (WMD: 0.00%, 95% CI: -0.10, 0.11, p = . 916) in the main analyses. In addition, changes to fasting blood glucose (FBG) levels were in favor of the control group (WMD: 1.19 mg/dl, 95% CI: 0.05, 2.34, p = .041). We found that giving grapes/grape products to adults might have beneficial effects on the HOMA-IR. Further, large-scale RCTs with longer duration are required to confirm these results.

Mens Sana in Corpore Sano: Does the Glycemic Index Have a Role to Play?

Although diet interventions are mostly related to metabolic disorders, nowadays they are used in a wide variety of pathologies. From diabetes and obesity to cardiovascular diseases, to cancer or neurological disorders and stroke, nutritional recommendations are applied to almost all diseases. Among such disorders, metabolic disturbances and brain function and/or diseases have recently been shown to be linked. Indeed, numerous neurological functions are often associated with perturbations of whole-body energy homeostasis. In this regard, specific diets are used in various neurological conditions, such as epilepsy, stroke, or seizure recovery. In addition, Alzheimer’s disease and Autism Spectrum Disorders are also considered to be putatively improved by diet interventions. Glycemic index diets are a novel developed indicator expected to anticipate the changes in blood glucose induced by specific foods and how they can affect various physiological functions. Several results have provided indications of the efficiency of low-glycemic index diets in weight management and insulin sensitivity, but also cognitive function, epilepsy treatment, stroke, and neurodegenerative diseases. Overall, studies involving the glycemic index can provide new insights into the relationship between energy homeostasis regulation and brain function or related disorders. Therefore, in this review, we will summarize the main evidence on glycemic index involvement in brain mechanisms of energy homeostasis regulation.

New and traditional foods in a modernized Mediterranean diet model

Mediterranean diet is definitely one of the healthiest dietary models. Next questions are: is the traditional Mediterranean diet adapted to the modern environmental and existential conditions? Could and/or should it be "modernized" to adapt to the various geographical, environmental, ethnic, and religious characteristics? If "modernization" is required, which traditional Mediterranean foods should be imperatively conserved as they are? Alternatively, which "new" foods-not traditional or not Mediterranean-could be introduced to help people to still respect the basic healthy Mediterranean diet principles? The present article intends to help solving these new questions.

Nutrition habits of children and adolescents with type 1 diabetes changed in a 10 years span

BACKGROUND

Diet plays a key role in the treatment of type 1 diabetes (T1D). Dietary habits changed rapidly in the last decades and few data are available on recent dietary changes in children and adolescents with T1D.

OBJECTIVE

To test the hypothesis that diet composition changed in a 10-year period in children and adolescents with T1D.

METHODS

Two hundred and twenty-nine T1D subjects (M/F:121/108) aged 6 to 16 years were recruited: 114 (group A) enrolled in 2009, not using CGM and/or CSII, and 115 (group B) enrolled in 2019. Anthropometric biochemical (HbA1c, lipid profile), diet, and insulin therapy parameters were compared between the two groups. Multivariate logistic regression analysis was performed with HbA1c as dependent variable (HbA1c > 58 mmol/mol = 1) and nutritional variables and technology use as independent ones.

RESULTS

Energy intake of group A was not statistically different from that of group B. Group B had a significantly (P < 0.001) higher protein and lipids intake and lower total carbohydrate and fiber intake than group A. HbA1c was significantly (P < 0.01) lower in group B than in group A. Logistic regression analysis showed that MUFA (OR 0.83, 95%CI:0.693-0.998), fiber intake (OR 0.82, 95%CI:0.699-0.0969), and technology use (OR 0.15, 95%CI:0.031-0.685), adjusted for age, gender, BMI, energy intake and diabetes duration, were associated with a HbA1c higher than 58 mmol/mol) (R² = 0.27, P < 0.05).

CONCLUSIONS

In a 10-year period, diet composition of children and adolescents with T1D changed and glucometabolic control improved. Fiber and MUFA intake showed a positive effect on HbA1c, independent from technology use, supporting the importance of educating children with T1D and families to maintain healthy eating habits.

Factors Beyond Carbohydrate to Consider When Determining Meantime Insulin Doses: Protein, Fat, Timing, and Technology

For many years, carbohydrate counting has been a popular strategy for determining mealtime insulin doses for people with diabetes who are on a multiple daily injection regimen or continuous subcutaneous insulin infusion. This approach assumes that only carbohydrate-containing foods and beverages affect postprandial glucose levels. However, many studies have indicated that the fat and protein content of a meal can play an important role in delaying postprandial hyperglycemia and should be considered when trying to optimize postprandial glucose levels. This article reviews research on making insulin dose adjustments for high-fat and high-protein meals, as well as the timing of mealtime insulin doses.

Is Extra Virgin Olive Oil an Ally for Women's and Men's Cardiovascular Health?

Noncommunicable diseases are long-lasting and slowly progressive and are the leading causes of death and disability. They include cardiovascular diseases (CVD) and diabetes mellitus (DM) that are rising worldwide, with CVD being the leading cause of death in developed countries. Thus, there is a need to find new preventive and therapeutic approaches. Polyphenols seem to have cardioprotective properties; among them, polyphenols and/or minor polar compounds of extra virgin olive oil (EVOO) are attracting special interest. In consideration of numerous sex differences present in CVD and DM, in this narrative review, we applied "gender glasses." Globally, it emerges that olive oil and its derivatives exert some anti-inflammatory and antioxidant effects, modulate glucose metabolism, and ameliorate endothelial dysfunction. However, as in prescription drugs, also in this case there is an important gender bias because the majority of the preclinical studies are performed on male animals, and the sex of donors of cells is not often known; thus a sex/gender bias characterizes preclinical research. There are numerous clinical studies that seem to suggest the benefits of EVOO and its derivatives in CVD; however, these studies have numerous limitations, presenting also a considerable heterogeneity across the interventions. Among limitations, one of the most relevant in the era of personalized medicine, is the non-attention versus women that are few and, also when they are enrolled, sex analysis is lacking. Therefore, in our opinion, it is time to perform more long, extensive and lessheterogeneous trials enrolling both women and men.

Amount and Type of Dietary Fat, Postprandial Glycemia, and Insulin Requirements in Type 1 Diabetes: A Randomized Within-Subject Trial

OBJECTIVE

The American Diabetes Association recommends individuals with type 1 diabetes (T1D) adjust insulin for dietary fat; however, optimal adjustments are not known. This study aimed to determine 1) the relationship between the amount and type of dietary fat and glycemia and 2) the optimal insulin adjustments for dietary fat.

RESEARCH DESIGN AND METHODS

Adults with T1D using insulin pump therapy attended the research clinic on 9-12 occasions. On the first six visits, participants consumed meals containing 45 g carbohydrate with 0 g, 20 g, 40 g, or 60 g fat and either saturated, monounsaturated, or polyunsaturated fat. Insulin was dosed using individual insulin/carbohydrate ratio as a dual-wave 50/50% over 2 h. On subsequent visits, participants repeated the 20-60-g fat meals with the insulin dose estimated using a model predictive bolus, up to twice per meal, until glycemic control was achieved.

RESULTS

With the same insulin dose, increasing the amount of fat resulted in a significant dose-dependent reduction in incremental area under the curve for glucose (iAUC_glucose) in the early postprandial period (0-2 h; P = 0.008) and increase in iAUC_glucose in the late postprandial period (2-5 h; P = 0.004). The type of fat made no significant difference to the 5-h iAUC_glucose. To achieve glycemic control, on average participants required dual-wave insulin bolus: for 20 g fat, +6% insulin, 74/26% over 73 min; 40 g fat, +6% insulin, 63/37% over 75 min; and 60 g fat, +21% insulin, 49/51% over 105 min.

CONCLUSIONS

This study provides clinical guidance for mealtime insulin dosing recommendations for dietary fat in T1D.

Insulin Management for Type 1 Diabetic Patients During Social Alcohol Consumption: The SPRITZ Study

BACKGROUND

There is no data available on the best insulin treatment to counteract the effects of glucose excursions due to a moderate alcohol intake associated with portions of slight fat and protein-containing food, as often the case during social happenings or "happy hours".

INTRODUCTION

This study analyzes the glycemic control and quality of life in 8 adult type 1 diabetic (T1D) patients on insulin-pump therapy which were invited to consume a traditional Italian aperitif ("Spritz" and chips).

METHODS

Patients consumed Spritz aperitif twice: using their habitual bolus, based on carbohydrates (CHO) counting (V1), or with a personalized, advanced bolus (V2) calculated from insulin/Kcal derived from Fats and Proteins (FPU). Post-prandial glucose was continuously monitored; glucose incremental areas (iAUC), glucose peak and time to peak, and estimated change from V1 to V2 from repeated- measures models were computed. Each patient fulfilled validated questionnaires on quality of life, knowledge about diabetes and CHO counting.

RESULTS

After the educational program, a reduced iAUC (0-80 min: -306, p=ns; 40-80 min: -400, p=0.07) due to greater (p=0.03) and prolonged double-wave insulin boluses was observed. Blood glucose peak and time to peak were also reduced. Moreover, improvements in the psycho-affective dimension, as well as in the alimentary knowledge were detected.

CONCLUSION

Therefore, a personalized educational program on CHO + FPU counting together with insulin bolus management can improve glycemic control during social consumption of alcohol, with positive reflections on the psycho-affective dimension. Further studies are mandatory to confirm such preliminary results.

A Mediterranean Diet Rich in Extra-Virgin Olive Oil Is Associated with a Reduced Prevalence of Nonalcoholic Fatty Liver Disease in Older Individuals at High Cardiovascular Risk

BACKGROUND

Adherence to a Mediterranean diet (MedDiet) is thought to reduce liver steatosis.

OBJECTIVES

To explore the associations with liver steatosis of 3 different diets: a MedDiet + extra-virgin olive oil (EVOO), MedDiet + nuts, or a control diet.

METHODS

This was a subgroup analysis nested within a multicenter, randomized, parallel-group clinical trial, PREvención con DIeta MEDiterránea (PREDIMED trial: ISRCTN35739639), aimed at assessing the effect of a MedDiet on the primary prevention of cardiovascular disease. One hundred men and women (mean age: 64 ± 6 y), at high cardiovascular risk (62% with type 2 diabetes) from the Bellvitge-PREDIMED center were randomly assigned to a MedDiet supplemented with EVOO, a MedDiet supplemented with mixed nuts, or a control diet (advice to reduce all dietary fat). No recommendations to lose weight or increase physical activity were given. Main measurements were the percentage of liver fat and the diagnosis of steatosis, which were determined by NMR imaging. The association of diet with liver fat content was analyzed by bivariate analysis after a median follow-up of 3 y.

RESULTS

Baseline adiposity and cardiometabolic risk factors were similar among the 3 treatment arms. At 3 y after the intervention hepatic steatosis was present in 3 (8.8%), 12 (33.3%), and 10 (33.3%) of the participants in the MedDiet + EVOO, MedDiet + nuts, and control diet groups, respectively (P = 0.027). Respective mean values of liver fat content were 1.2%, 2.7%, and 4.1% (P = 0.07). A tendency toward significance was observed for the MedDiet + EVOO group compared with the control group. Median values of urinary 12(S)-hydroxyeicosatetraenoic acid/creatinine concentrations were significantly (P = 0.001) lower in the MedDiet + EVOO (2.3 ng/mg) than in the MedDiet + nuts (5.0 ng/mg) and control (3.9 ng/mg) groups. No differences in adiposity or glycemic control changes were seen between groups.

CONCLUSIONS

An energy-unrestricted MedDiet supplemented with EVOO, a food with potent antioxidant and anti-inflammatory properties, is associated with a reduced prevalence of hepatic steatosis in older individuals at high cardiovascular risk.

The Effect of Two Types of Pasta Versus White Rice on Postprandial Blood Glucose Levels in Adults with Type 1 Diabetes: A Randomized Crossover Trial

Background: Food choices are essential to successful glycemic control for people with diabetes. We compared the impact of three carbohydrate-rich meals on the postprandial glycemic response in adults with type 1 diabetes (T1D). Methods: We performed a randomized crossover study in 12 adults with T1D (age 58.7 ± 14.2 years, baseline hemoglobin A1c 7.5% ± 1.3%) comparing the postprandial glycemic response to three meals using continuous glucose monitoring: (1) "higher protein" pasta containing 10 g protein/serving, (2) regular pasta with 7 g protein/serving, and (3) extra-long grain white rice. All meals contained 42 g carbohydrate; were served with homemade tomato sauce, green salad, and balsamic dressing; and were repeated twice in random order. After their insulin bolus, subjects were observed in clinic for 5 h. Linear mixed effects models were used to assess the glycemic response. Results: Compared with white rice, peak glucose levels were significantly lower for higher protein pasta (-32.6 mg/dL; 95% CI -48.4 to -17.2; P < 0.001) and regular pasta (-43.2 mg/dL, 95% CI -58.7 to -27.7; P < 0.001). The difference between the two types of pastas did not reach statistical significance (-11 mg/dL; 95% CI -24.1 to 3.4; P = 0.17). Total glucose area under the curve was also significantly higher for white rice compared with both pastas (P < 0.001 for both comparisons). Conclusions: This exploratory study concluded that different food types of similar macronutrient content (e.g., rice and pasta) generate significantly different postprandial glycemic responses in persons with T1D. These results provide useful insights into the impact of food choices on and optimization of glucose control. Clinical Trial Registry: clinicaltrials.gov NCT03362151.

Postprandial glucose response after the consumption of three mixed meals based on the carbohydrate counting method in adults with type 1 diabetes. A randomized crossover trial

BACKGROUND & AIMS

People on intensive insulin therapy usually calculate their premeal insulin dose based on the total amount of consumed carbohydrates. However, arguments have been expressed supporting that also the protein and fat content of the meals should be considered when estimating premeal insulin dose. We examined the effectiveness of the carbohydrate counting method after consumption of mixed meals, and we further explored the effects of added extra virgin olive oil in these mixed meals, in adults with type 1 diabetes.

METHODS

Twenty adults (35.0 ± 8.9 years, BMI 27 ± 5 kg/m²) with diabetes duration 17 ± 11 years, on intensive insulin therapy with multiple injections, consumed 3 mixed meals (pasticcio, chicken with vegetables and baked giant beans), with and without the addition of 11 ml extra virgin olive oil (total of 6 meals), in random order, with the insulin dose determined by using the carbohydrate counting method. Capillary blood glucose was measured at premeal (baseline) and 30, 60, 90, 120, 150 and 180 min after meal consumption. At every visit, participants were assessed for anthropometric parameters and subjective stress.

RESULTS

Participants had mean HbA1c 7.5 ± 1.2%, mean carbohydrate to insulin ratio 9:1 IU and stable body weight, waist circumference and subjective stress throughout the study. The mean glucose concentration, for all 6 meals, 120 min postprandially was within target (<180 mg/dl) in nearly 80% of the sample. Addition of olive oil produced sustained increased postprandial glucose concentrations only to pasticcio meal, although within target, and no significant differences were noticed for the grilled chicken with vegetables or the baked giant beans (legume) meals.

CONCLUSIONS

The carbohydrate-counting method was effective for achieving postprandial glucose levels within target threshold up to 3 h postprandially. Moreover, adding small amounts of dietary fat (extra virgin olive oil) to low fat meals does not significantly alter the postprandial response within the first 3 h, whereas caused a sustained increase in postprandial blood glucose concentrations to the high energy density meal (i.e. the pasticcio meal).

Gastrointestinal effects of extra-virgin olive oil associated with lower postprandial glycemia in type 1 diabetes

OBJECTIVE

To explore the possible mechanisms behind the lower glycemic response observed when extra-virgin olive oil (EVOO) is added to a high-glycemic index meal in patients with type 1 diabetes (T1D).

RESEARCH DESIGN AND METHODS

According to a randomized cross-over design, eleven T1D patients (6 women, 5 men) on insulin pump consumed in the metabolic ward, one week apart, three high-glycemic index meals differing only for amount and quality of fat: high-monounsaturated fat (EVOO), high-saturated fat (Butter), and low-fat (LF). Before and after the meals, blood glucose (continuous glucose monitoring), gastric emptying rate (ultrasound technique), and plasma concentrations of glucagon-like peptide 1 (GLP-1) and glucose-dependent insulinotropic polypeptide GIP (ELISA), glucagon (RIA), and lipids (colorimetric assays) were evaluated.

RESULTS

Blood glucose iAUC (mmol/lx360 min) was lower after the EVOO (690 ± 431) than after the Butter (1320 ± 600) and LF meals (1007 ± 990) (M ± SD, p = 0.041 by repeated measures ANOVA). Gastric antrum volume was significantly larger in the early (60-90 min) postprandial phase (106 ± 21 vs. 90 ± 16 ml, p = 0.048) and significantly smaller in the late phase (330-360 min) (46 ± 10 vs. 57 ± 22 ml, p = 0.045) after the EVOO than after Butter meal. EVOO significantly increased postprandial GLP-1 iAUC (261 ± 311) compared to Butter (189 ± 349) (pmol/Lx180 min, p = 0.009). Postprandial GIP and glucagon responses were not significantly different between EVOO and Butter. Postprandial triglyceride iAUC was significantly higher after EVOO (100 ± 53) than after Butter (65 ± 60) (mmol/l × 360 min, p = 0.048).

CONCLUSIONS

Changes in gastric emptying and GLP-1 secretion and reduced glucose absorption through glucose-lipid competition may contribute to lower glycemia after a high-glycemic index meal with EVOO in T1D patients.

CLINICAL TRIALS NUMBER

NCT02330939.

The Effect of Added Peanut Butter on the Glycemic Response to a High-Glycemic Index Meal: A Pilot Study

OBJECTIVE

The purpose of this pilot study was to determine whether supplementation of a high-glycemic index breakfast meal with peanut butter attenuates the glycemic response.

METHODS

Sixteen healthy adults, aged 24.1 ± 3.5 years, reported in the morning to a nutrition assessment laboratory for two days of data collection, having fasted 8 to 12 hours. On day 1 (control), fasting blood glucose (BG) was measured using glucometers, then participants consumed two slices of white bread and 250 mL apple juice (60 g carbohydrate) within 15 minutes. BG was measured again at 15, 30, 60, 90, and 120 minutes after the first bite of the meal. On day 2, the protocol was repeated, except 32 g (2 tbsp) of peanut butter was added to the meal (treatment).

RESULTS

The spike in BG was significantly lower on the treatment versus control day (35.8 ± 16.4 vs. 51.0 ± 20.8 mg/dL, respectively; p < 0.01), and BG was significantly lower on the treatment day at 15, 30, and 60 minutes post-meal consumption (p < 0.05).

CONCLUSIONS

This study indicates that supplementation with 32 g (2 tbsp) peanut butter attenuates the magnitude of BG spike and overall glycemic response to high-glycemic index meal and may be a practical, beneficial strategy to prevent undesirable elevations in BG.

Modalities for assessing the nutritional status in patients with diabetes and cancer

Epidemiological data have shown that an increased body mass index (BMI) is associated with a higher risk of various cancers, especially in obese diabetic patients. However, oncologic patients often present nutritional alterations that can worsen their prognosis. The aim of this review is to propose the use of cheaper and easy to use tools to assess the nutritional status of patients with cancer with altered glucose metabolism. Based on a literature review, we propose anthropometric measures to classify the degree of malnutrition. Moreover, the Karnofsky Performance Status (KPS) and the Eastern Cooperative Oncology Group's performance index (ECOG) are useful to assess the functional status of the body; the achievement of nutritional needs can be analysed with the PG-SGA questionnaire, while the quality of life can be investigated using the DTSQ, SF36, EQ-5D questionnaires and the Edmonton Symptom Assessment System. Pre-albumin dosage and lymphocyte count are proposed as nutritional parameters. The degree of hydration can be evaluated through the Bio-Impedance Test (BIA), and energy intake through the dairy food diary, which considers the type of nutrition and the consistency of the meals. It is possible to use a score for each tool used, which is useful to plan an adequate nutritional intervention.

Dietary Fibre as a Unifying Remedy for the Whole Spectrum of Obesity-Associated Cardiovascular Risk

Obesity is a pandemic carrying the heavy burden of multiple and serious co-morbidities including metabolic syndrome, type 2 diabetes and cardiovascular diseases. The pathophysiological processes leading to the accumulation of body fat slowly evolve to fat accumulation in other body compartments than subcutaneous tissue. This abnormal fat deposition determines insulin resistance which in turn causes blood glucose and lipid metabolism derangement, non-alcoholic fatty liver disease, hypertension, and metabolic syndrome. All these conditions contribute to increase the cardiovascular risk of obese people. Several randomized clinical trials demonstrated that moderate weight loss (5⁻10%) in obese patients improves obesity-related metabolic risk factors and coexisting disorders. Therefore, nutritional strategies able to facilitate weight management, and in the meantime positively influence obesity-associated cardiovascular risk factors, should be implemented. To this aim, a suitable option could be dietary fibres that may also act independently of weight loss. The present narrative review summarizes the current evidence about the effects of dietary fibres on weight management in obese people. Moreover, all of the different cardiovascular risk factors are individually considered and evidence on cardiovascular outcomes is summarized. We also describe the plausible mechanisms by which different dietary fibres could modulate cardio-metabolic risk factors. Overall, despite both epidemiological and intervention studies on weight loss that show statistically significant but negligible clinical effects, dietary fibres seem to have a beneficial impact on main pathophysiological pathways involved in cardiovascular risk (i.e., insulin resistance, renin-angiotensin, and sympathetic nervous systems). Although the evidence is not conclusive, this suggests that fibre would be a suitable option to counteract obesity-related cardio-metabolic diseases also independently of weight loss. However, evidence is not consistent for the different risk factors, with clear beneficial effects shown on blood glucose metabolism and Low Density Lipoprotein (LDL) cholesterol while there is fewer, and less consistent data shown on plasma triglyceride and blood pressure. Ascribing the beneficial effect of some foods (i.e., fruits and vegetables) solely to their fibre content requires more investigation on the pathophysiological role of other dietary components, such as polyphenols.

Oleuropein, a component of extra virgin olive oil, lowers postprandial glycaemia in healthy subjects

AIMS

Extra virgin olive oil lowers postprandial glycaemia. We investigated if oleuropein, a component of extra virgin olive oil, exerts a similar effect on postprandial glycaemia and the underlying mechanism.

METHODS

Twenty healthy subjects were randomly allocated in a cross-over design to 20 mg oleuropein or placebo immediately before lunch. Postprandial glycaemia along with blood insulin, dipeptidyl-peptidase-4 (DPP-4) and glucagon-like peptide-1 and oxidative stress, which included soluble NADPH oxidase-derived peptide activity (sNox2-dp), 8-iso-prostaglandin-2α and platelet p47^phox phosphorylation, were analysed before and 2 h after meal.

RESULTS

After 2 h, subjects who assumed oleuropein had significantly lower blood glucose, DPP-4 activity and higher insulin and glucagon-like peptide-1 compared to placebo. Furthermore, sNox2-dp, 8-iso-PGF2α and platelet p47^phox phosphorylation were significantly lower in oleuropein- compared to placebo-treated subjects. DPP-4 significantly correlated with sNox2-dp [Spearman's rho (Rs) = 0.615; P < 0.001], p47^phox phosphorylation (Rs = 0.435; P < 0.05) and 8-iso- prostaglandin-2α (Rs = 0.33; P < 0.05). In vitro study demonstrated that hydroxytyrosol, a metabolite of oleuropein, significantly reduced p47^phox phosphorylation and isoprostane formation.

CONCLUSIONS

These findings indicate that oleuropein improves postprandial glycaemic profile via hampering Nox2-derived oxidative stress.

Mediterranean Eating Pattern

IN BRIEF The Mediterranean-style eating pattern (MEP) has long been touted as a healthful way of eating. However, the health benefits of the eating pattern and key elements contributing to those benefits are still being researched. In people with type 2 diabetes, the majority of studies report that the MEP improves glycemic control and cardiovascular risk factors. In people at risk for diabetes, the majority of studies report a protective effect of the MEP against the development of type 2 diabetes. Although more research is needed to determine whether study results can be achieved outside the Mediterranean geographical region, and especially in the United States, the high-quality individual foods and combinations of foods included in the MEP can be recommended as a healthful eating approach.

Micronutrient Intake in a Cohort of Italian Adults with Type 1 Diabetes: Adherence to Dietary Recommendations

Micronutrients are of fundamental importance in maintaining health status. However, data on their dietary intake are few particularly in persons with diabetes. The aim of this study was to evaluate in adults with type 1 diabetes (T1DM) attending a tertiary-level diabetes center in Southern Italy the intake of micronutrients (both vitamins and minerals) and the adherence to recommendations. Seven-day food records of 60 T1DM patients were analyzed. Micronutrient intake was evaluated based on the Italian food composition tables and expressed as amount per 1000 kcal of energy intake to adjust for possible underreporting. Adherence to recommendations for vitamins A, B₆, B₁₂, and C and niacin was acceptable in both sexes (ranging from 77% to 100%). Half of the patients did not adhere to folate recommendation, even less to vitamin E, and no patient reached the recommended intake for vitamin D. As for minerals, adherence was low for potassium and selenium (0-23%); intermediate for zinc, copper, and magnesium; low and intermediate for calcium in men and women, respectively; and low for iron in women. In conclusion, the diet followed by T1DM patients may not have a sufficient content of different micronutrients. Therefore, an adequate intake of low-fat dairy products, fish, legumes, and vegetables should be encouraged as components of a healthier dietary pattern.